The former world No. 3 retired mid-match on Day 1, and says his ongoing back injury may force him to reconsider his tennis future.

The 62-year-old was able to leave the venue by herself—holding an ice pack provided by Zverev to her neck—after the board fell from the upper tier of the stadium into the crowd on the lower tier.

Purists decried the tradition-busting plan, but top players are on board to compete.